Golf aficionados have long desired to identify and personalize golf balls for various reasons. Identification of the ball is required in official play. Most golfers mark balls to ensure that they have found and played the correct one. Balls can be marked with an alignment line around the circumference of the ball to orient the ball and as a reference mark and aid. And, as printing techniques and digital camera technology have advanced, golfers have desired digital photos, graphics or some type of decorative logo to be printed on the outer surface of the ball designed, for example, to advertise or identify a particular corporate entity, golf course, club, or resort, or as a remembrance or memento or souvenir of a place, an event or a special person.
Existing techniques for printing on a curved, non-planar surface such as a golf ball are limited, not timely and are not economically feasible when the quantity to be printed is less than a few dozen. One technique has been to apply a decal to the surface of the ball and then to spray the ball with a clear overcoat surface. The use of decals, though, can be troublesome and applying anything that affects the flight of a golf ball is not allowed by the Professional Golf Association. Decals are typically produced using a silk-screen process and are expensive for small quantity orders. The application of the decals and then subsequent clear overcoat is labor-intensive and thereby costly.
Another technique for printing text and graphics on curved objects is pad printing as disclosed in U.S. Pat. No. 5,537,921 to Adner et al., U.S. Pat. No. 5,806,419 to Adner et al., and U.S. Pat. No. 5,778,793 to Mello et al. The pad printing technique involves the use of a printing plate engraved or photo-etched with an image pattern. Ink applied to the printing plate is then transferred to a flexible pad placed in contact with the printing plate. The pad is then removed from the printing plate and then placed in contact with the surface to be printed, such as the surface of a golf ball.
Pad printing has many shortcomings for printing an image on a small quantity of objects. The fabrication of a printing plate requires that an image be developed and transferred, either by engraving or by a photographic process, to the plate. The plate itself can be expensive and transferring an image to the plate is time consuming. For every new image to be printed on an object, a new plate must be fabricated and mounted into the pad printing system. The lead-time required to proof the artwork by the customer and produce the printing pad is generally weeks and not available to individuals at home or in a retail setting.
U.S. Pat. No. 5,831,641 to Carlson describes another system for printing text and graphics on an object. This system discloses the use of an ink jet plotter and a mechanism to hold, position, and rotate the object. Ink jet plotting basically involves a process whereby ink particles are projected in a continuous stream toward the surface to be imprinted using appropriate computer control to create text and graphics on the printing surface. The ink jet plotter moves along a linear axis with the object positioned so that the surface of the object presents a planar surface to the ink jet plotter. This method of applying images is limited to objects with a surface that can be positioned so that the surface is parallel to the travel axis of the ink jet plotter. Although this system can be advantageous for applying an image to a small number of objects, many curved objects, such as balls and ornaments, do not present planar surfaces upon which an image can be applied.
U.S. Pat. No. 6,538,767 to Over et al. describes a system for printing on spherical and semi-spherical objects using a plurality of print heads, a graphics unit containing one or more ink jet printers and one or more drying stations. This system, as explained in the patent, overcomes the disadvantages of the contact printing techniques described above and the limitations of the Carlson patent. This system involves the use of a fixture to position and rotate an object and a control unit for moving the graphics unit so that the graphics unit is maintained at a desired position relative to the object as the graphics unit applies the image to the object. The graphics unit is also movable in an arc relative to the object so that an image can be applied around the perimeter of the object as it is rotated in the fixture. The image to be applied is separated into tracks and the graphics unit successively applies the image tracks to individual tracks on the object as it is rotated.
The system described in the Over patent has several limitations. The graphics unit moves in an arc relative to the object as the object is rotated along its axis a designated distance from the graphics unit. Each station and associated graphics unit applies a single color. After the application of an individual color at its dedicated station the object must be dried by ultraviolet light at a dedicated drying station. An image that consists of multiple colors requires that an object be moved from graphics unit to graphics unit and results in a complex and expensive system. Rotating the object, moving the graphics unit in an arc relative to the object, and then moving the object from graphics unit to graphics unit necessitates a complex control unit. The image preparation for printing requires a spherical transformation and the associated data tracks which necessitate a trained operator. This process still requires time to interact with the customer to approve the graphics before they can be applied.
Another U.S. Pat. No. 5,832,819 to Widman describes a “method for transferring an image onto an object having curved surfaces”, title, that requires the target surface be substantially flattened by pressing or separating a surface layer, followed by heat being applied to the surface. Furthermore, the object must be later cooled in water and then alcohol. The flattening and heating process required by this process can potentially harm and even destroy some objects such as golf balls. Also, the mechanical steps, and later steps of immersion in water and alcohol require further undesirable and time consuming steps that would not be practical to users of the process.
Thus, the need exists for solutions to the above problems.